@mydarkcity : Surprisingly, I managed also to sit through a World Cup game without getting kicked off every 30 seconds. Just bounced out once during an entire game, but got back in with no further problem.
Regarding the account and provider logins, I had tried that a few days ago but it didn't work for me. The problem persisted and I was constantly being bounced out..
But as I said, it worked for a full game - so maybe (somehow?) they addressed the issue. Keeping my fingers crossed.
As an FYI, during the days that FoxSports was kicking me out on Roku, accessing FoxSports through Amazon Fire TV worked no problem. (Just in case this issue persists...)